Ok, let me jump in and answer a few questions:
1. How easy is it to get permabanned? Very, depending on what you do. Spambots, advertisers, ban-jumpers, porn posters, and the like get a first class ticket to Banville as soon as we spot them. For other infractions - say, your typical troll - you generally need to show a pattern of behavior. Most folks are capable of losing their temper and doing something stupid once or twice, and while they'll get slapped for it, they typically won't get permabanned.
2. How do you get unbanned (once you've been permabanned)? You don't. Permaban means we don't want you here. You've broken our rules to the extent that you are no longer welcome in our community. Period, the end. Other bans may be overturned by appeal (i.e., you basically explain your side of the story, and if we see your point, we lift the ban), or you can simply just wait them out. But once you've been shown the door, we really have no interest in letting you back in.
And Max didn't ask to be banned, he simply was banned. He did, however, thank us for it.